L6 Clutch

Discussion in 'Drag Racing' started by merc72, Jan 21, 2013.

  1. merc72

    merc72 Member

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    In my Comet I have built the six up some, lotta head work, cam [290], 2v carb, Header & big exhaust..Since I have the trans and Bell out for a T5z install should I think about replacing the clutch? The present clutch is a 9" long style and while it seems able to handle the extra power I'd hate to have to replace it later..There isn't room to go to a 10"..I managed to find something in RAM but not for modified engine/racing, 9" Diafram..The flywheel has extra bolt holes, not tapped..Any suggestions?
     
  2. Bryant

    Bryant forgot more than learned

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    call a couple clutch companies. we have a local clutch shop here (southland Clutch) that can make custom clutches.
    you should at the least be able to get a dual friction disk made and new pressure plate.
     
  3. merc72

    merc72 Member

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    After many calls I settled on a clutch from RAM through Must Unlimited..Diafram and to my surprise a metalic six puck disc, MU garentees it for 50k..I had to redrill the flywheel and PP to 3/8, and do the dowel pin holes..The problem is in the clutch linkage, I retained the stock linkage..1" free play and then next 1" the pedal pressure rises and falls to a tolerable level to the floor..Unfortunately when you let it out engagement is right when pedal pressure takes a rise in that 1" and makes engagement an all or nothing deal..Any clues, long style clutch originally..
     
  4. Bryant

    Bryant forgot more than learned

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    sounds like the new clutch has a different height. they make adjustable pivot balls for the clutch fork. i suspect you need one of these to get the geometry correct with the new clutch.
     
  5. Fordmaster169

    Fordmaster169 Member

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    OK, it is a 6 puck clutch!!!!!!!!!!!!!!!! That is the way they work, not so friendly on the street. But they sure do nice on the track.
     
  6. merc72

    merc72 Member

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    No pivot ball in my system, old style with z-bar..When I put the linkage back in everything was fine even free play was ok but the 1" of sharp rise and fall I knew was going to be rough..I drilled another hole in the z-bar closer to the pivot point [making more ratio] and it became tolerable but the snap action sucks. I'm pretty sure its in the linkage somewheres or the helper spring under the dash [which is a pain to R&R]...
    I relise there is no marcel in the disk so the take up will be sharper but I think [re want] I should have more conrol..
     
    Last edited: Jun 18, 2013
  7. merc72

    merc72 Member

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    Here is where I'm at so far:
    I figured a way to remove the under dash clutch helper spring with out hurting myself and it made a good difference in removing the over center feel in trying to release the clutch and effort was/is very tolerable...Now its a matter of adjusting ratio slightly and adjusting free play to make the clutch grab a little lower and shiming the pedal stop to take free play out if it is too much, at least I have direction now....The paddle disc behaves much better than I thought it would as long as starts are made a little on the aggressive side..
     
  8. merc72

    merc72 Member

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    Today I made an adition to the Z bar lower arm, adding another peice to the forward edge with a bunch of holes to try different ratios..While under there I figured I'd try to see why the speedo stopped working..Disconnect cable at speed reducer at trans, cable seemed to be in one peice and not dragging or bound up..Took the speed reducer off and it too seemed good..Speedo gear was good..Looked into trans hole and the drive gear has moved out of position, towards the rear; I guess the clip thats supposed to hold it has failed..Now I suppose I'll have to take the trans out to fix it, dunno where the clip [or remains] is..This is all getting old and tiring..
     
  9. merc72

    merc72 Member

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    I took the trans out today, and got the tailhousing off..Found the speedo gear clip hidding in a little nook in the rear of the main case..Whew, glad it stayed out of fifth gear :mad:..Its probably my fault it came out :( as I removed the speedo gear to change the fifth gear set and put the original clip back in, maybe its supposed to be a one time use? I'll make a drive key, with a pin to fit the hole in the mainshaft and a lip at one end [front] to locate the gear and a clamping collar at the rear since thats the load direction..I'd hate to trust another clip...:confused:
     
  10. Gene Fiore

    Gene Fiore Member

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    Hey merc72...what are the specs on your engine and what kind of head work did you do?
     
  11. merc72

    merc72 Member

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    Made a replacement gear retaining clip and put trans back together and in car..Z bar and linkage all in and adjusted at lower ratio and makes for a lot of pedal free play; if the ratio [or where ever it ends up] is satisfactory I'll shim the pedal stop if the extra free play annoys me..
     
  12. merc72

    merc72 Member

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    Here is the first build above stock:
    200 cube, factory rotating assy.. Clifford HD timing chain, Isky 280° cam [.440 lift] and Springs, Retainers, Keepers, Clifford HD pushrods and Ford Adjustable rockers..Head milled .050; I started with a brand new head but don't remember if I got a 72' 200 ci or the later 250 ci with bigger valves...Relieved around intake valve to head gasket and Three angle valve job on all valves..Blended valve bowls and opened up the runners to the log as much as I dared and then some, spent a lot of time getting a good radius at the runner log junction, especially carb side..Opened up exhaust ports and installed center divider..I opened up the carb hole as much as I could with out losing the original gasket surface [so I had material left for good radius into log] and then an aluminum adaptor for a 500 Holley 2v, blending from manifold hole size to carb throttle plate size...Hooker headers, dual exhaust and a DC Ignition distributor..

    AS of now: Removed 500 Holley [no low end, bog city on fast starts] for 350 Holley, great low end and fast starts, can control wheel spin with throttle...Removed whole exhaust..Made an exhaust [spider] manifold out of sheet metal plates sizing runners as best I could to end up with six into one 2-1/2" outlet..2-1/2" exhaust to Flowmaster [40 series, maybe] with two 2" out to bumper.. All else is the same...
     
  13. merc72

    merc72 Member

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    Up date to clutch linkage, made new arm off of equiliser link for less movement at arm.. Adjusted to maintian some throw out brg clearence which made the free play at pedal a mile long..Shimmed pedal stop to bring free play back in to 1" zone...Not the greatest but will do a few other things that I think will help..Clutch sure shifts nice, instant release..I'll up date come spring with new tries..Seb..
     

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